A highly efficient, diastereo-and enantioselective route was developed to access a great variety of lignans. The asymmetric synthesis of the 2,3-disubstituted g-butyrolactones 9a-c could be improved in the case of aldol reactions by employing 2.2 equivalents of LiCl as an additive to provide, after purification, highly diastereo-and enantioenriched starting materials for the synthesis of the furofuran lignans (-)-methyl piperitol, (-)-sesamin, and (-)-aschantin. Furthermore, the g-butyrolactone 15 was converted into dibenzylbutyrolactone lignan (+)-yatein, the dibenzylbutandiol type (+)-dihydroclusin, the tetrahydrofuran type (+)-burseran, and the dibenzocyclooctadiene type (-)-isostegane.

Starting from chiral α‐amino nitriles (S,S,R/S)‐3, we prepared β‐aroyl‐γ‐butyrolactones (S)‐5 as well as 2,3‐disubstituted γ ‐butyrolactones (S,S)‐ or (R,S,R)‐6 in high yields and with high enantiomeric excesses by conjugate addition to butenolide, followed by protonation, α‐alkylation or α‐aldol addition, respectively. The introduction of one up to three stereogenic centers opens a flexible and highly efficient diastereo‐ and enantioselective route to 2,3‐dibenzylated γ‐butyrolactones 6, which proved to be important lignan building blocks.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.